#include <bits/stdc++.h>
#define REP(i, n) for(int i = 0; i < n; i++)
#define REPR(i, n) for(int i = n; i >= 0; i--)
#define FOR(i, m, n) for(int i = m; i < n; i++)
#define INF 2e9
#define ALL(v) v.begin(), v.end()
using namespace std;
typedef long long ll;
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    vector<pair<int, string>> h(3);
    int temp;
    cin >> temp;
    h[0] = make_pair(temp, "A");
    cin >> temp;
    h[1] = make_pair(temp, "B");
    cin >> temp;
    h[2] = make_pair(temp, "C");

    sort(ALL(h), greater<pair<int, string>>());

    REP(i, 3){
        cout << h[i].second << endl;
    }

}